The invention relates generally to a stroke-controlled windshield wiper unit for motor vehicle and more specifically to a wiper unit having a gear casing, including a stroke mechanism of the wipers which is rotationally solidly screw connected to a drive unit by a drive shaft rotationally solidly connected to the stroke mechanism of the wiper.
A windshield wiper unit of this type is shown in German Patent Specification No. 2,417,128. In this case, the gear casing is mounted to the drive unit before mounting to the vehicle.
The fitting of such a windsheld wiper unit can involve difficulties if the drive unit has to be fitted into the vehicle first and the gear casing is only fitted subsequently. Under certain circumstances, the internal screw connection of the gear housing and drive shaft to the drive unit cannot be reached or can only be reached with difficulty.
Thus, it is an object of the present invention to provide a windshield wiper unit wherein the gear casing can also be fitted directly as the conclusion of an assembly operation. Another object is to provide a windshield wiper unit that allows fitting and removal without difficulty in cases where a vehicle windshield has already been installed.
These and other objects are achieved in accordance with the invention with the drive shaft being a hollow shaft which accepts a threaded bolt passing through it, the head of which bolt being located at the gear casing head. The drive shaft and the drive unit have intermeshing splines to form the solid rotational connection. Means are provided for limiting axial displacement of the drive unit when it is being screwed to the gear casing by the bolt. A hexagon socket is provided in the head of the bolt. Thus, the gear casing, stroke mechanism and drive shaft may be fitted to the drive unit easily at any stage of installation.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.